William hassall



W. HASS L REFRACTORY GAS B LG CK FOR FLUES APPLICATI 12.1919.

1 1,822., Patented Nov. 18, 1919.

Futon.

wILInAM I-IASSALL, or WOODVILLE, nonron-on-rnnnr, ENGLAND.

REFRACTORY GAS-BURNING BLOCK FOR FLUES.

Application filed September 2, 1919.

To all whom it may concern:

Be it known that I, WILLIAM HAssALL, a subject of the King of Great Britain and Ireland, residing at Tresco House, Woodville, Burton-on-Trent, Staffordshire, England, have invented certain new and useful Improvements in Refractory Gas-Burning Blocks for Flues, of which the following is a specification.

This invention relates to fines of boilers of the Lancashire or such like type, and has for its object the provision of improved means for maintaining the temperature in the flue (which in thistype is substantially horizontal) at a sufficient intensity to cause complete combustion therein of the gases and combustible particles passing with the flame from one end to the other and at the same time directing the flame so as to keep it well in contact with the wall of the flue instead of letting it pass mainly along a central course and escaping as smoke wlthout imparting its full heat to the boiler- The accompanying drawings illustrate the invention, in which Figure l is a longitudinal section of the rear end of a furnace provided with the same, and Figs. 2 and 3 are a front elevation and a longitudinal section respectively of a block hereinafter described.

Referring to the said drawings, a fireclay block B is provided which is cylindrical or tapered in its length and has a circumference and cross section corresponding with, but smaller than, the bore of the flue D, which in this example is circular. One face of the block B is concave, as shown at C. This block is supplied with feet A and radial stays A to keep it concentric in the flue D, and is placed therein, at or near the end farthest from the fire boX with its concave face C facing toward the latter, leaving a practically clear annular passage E between it and the flue walls. This annular passage E is tapered in the longitudinal direction, in the example illustrated, but I do not limit myself to such tapering. It may be parallel with the flue, but if the block is made of gradually increasing diameter, toward its rear the annular passage E is gradually constricted- The block B, when in position, has the eflect of directing the flames toward the Specification of Letters Patent.

Patented Nov. 18, 1919.

Serial No. 321,277.

walls of the flue D, as the flames will have to pass through the annular passage E surrounding it. If this passage is tapered, as mentioned, it will more effectively draw the burnt dust out-of the boiler flue D and especially out of the said passage and the parts directly behind it. There will necessarily be some suction in all parts of the rear end of fine D; but it will be most effective just behind passage E thereby preserving a more regular working draught than if the block be cylindrical and, therefore, parallel in the longitudinal lines of its surface to the wall of the fine The block B will soon become intensely heated and will then radiate and reflect heat from its con cave face C along the flue D, thus 1naintaining the gases or products therein at a very high temperature indeed keeping them uninterruptedly in a state of complete combustion- In order to assist the placing of the block B in position it is built up of several parts fitted together, the joints being indicated in Figs. 2 and 3 by straight lines 6 Z). This enables the individual pieces composing the block B to be passed into the flue D one by one and assembled in the flue to form the block. This subdivision will not only prove useful in application but will provide a safeguard against cracking and breakage. It could even be utilized for replacing a damaged portion of the block.

Modifications may be made in its construction, without departing from the essential principles of the invention.

Although one of such blocks B- placed at the farther end of the flue is generally found to be suflicient, nevertheless, one or more other similar blocks may be placed in suitable parts of the flue and, if desired, these may vary in size, according to the positions they occupy, and the elfect desired.

They are applicable to furnaces with induced or forced draft as well as to those with ordinary natural draft, and may be fixed permanently if desired.

With a forced draft the heat may be increased by using blocks of such an increased size as to reduce the annular spaces around them to small proportions, increasing the pressure accordingly. More heat will there-- by. be transmitted through the walls of the flue into the Water in the boiler.

In combination with a flue a solid heat accumulating block of refractory material arranged therein, said block being provided with a concave face on the side presented to the flames and of less maximum diameter than that of said flue, also tapering from its rear face to said concave face and being pro- 10 vided with means for spacing it from said fine.

In testimony whereof I have sighed my name to this specification- VVILLIAM HASSALL. Witnesses ARTHUR SnU'r'rLmvoR'rn, JAMES KIRBY. 

